基于靶式和悬臂梁的FBG流量/温度同时测量研究

FBG sensors combining target with cantilever beam for simultaneous measurement of Flow-rate/temperature

提出一种基于靶式结构和悬臂梁结合的新型流量/温度同时测量的光纤Bragg光栅(FBG)传感器。当流体流过传感器,流速的变化引起圆形靶产生应变,应变传递到等强度悬臂梁1上,进而引起粘贴其上的FBG1波长发生改变,而粘贴在悬臂梁2上的FBG2波长不发生改变;流体温度发生变化会引起FBG1、FBG2波长同时发生改变,且波长改变相同;通过测量两光栅的波长,得到流体的流量和温度。在水和蓖麻油实验得到:传感器的流量测量范围分别是400～2200cm3/s和700～1800cm3/s,温度测量范围是0～100℃。

A novel FBG sensor for simultaneous discriminating measurement of flow-rate and temperature is developed based on target and cantilever beams.While fluid passes through the sensor,the change of flow velocity in the pipeline results in the strain change of target stucture,and then the strain transmits on cantilever beam,the wavelength of FBG1 on it is changed but the wavelength of FBG2 on the other cantilever beam isn′t changed.While the change of temperature of fluid results in the wavelength changes of FBG1 and FBG2 at the same time.The flow-rate and temperature of fluid can be measured by testing the reflective wavelength change of FBG1 and FBG2.The experimental results in water and in castor oil pipeline verify the feasibility of the proposed sensor with a flow-rate measurement range of 400-2 200 cm3/s,700-1 800 cm3/s and temperature range of 0-100 ℃,respectively.